True to Life Psychology?

So I'm in the midst of writing what I'm calling a police fiction.
Essentially, what it is; is following the on and off duty lives of three characters, who have only one thing in common- their employer- the police.
Anyways, one thing that is prominent in each character's stories is how their past and current state of mind effects their judgment. An example would be this: I have one character whose fiance passed away, so he's nervous about starting a new relationship with someone else.
(That's just the tip of the iceberg, btw.)

Obviously there's a lot of character psychology going on, and one of them is actually seeing a psychologist for what's happening in her life.
My question is- how true to life should I keep the psychology? It does play a big part of the story, but I use it more as a device for the audience to show that the cops they are reading about are more than just a badge and a gun; that there is more going on in their lives that we realize.
(Sorry for the long post.)

Sent from Samsung Galaxy S4 Using Tapatalk

__________________

"If I knew then what I know now, I'd stay six years old." -"Thrones" by Alexisonfire